An optical pickup device used for an optical disk apparatus has on an optical base, a light emitting element that generates a laser light, an objective lens for condensing the laser light and applying the same onto an optical disk, and a light receiving element that receives reflected light from the optical disk. The optical base is positioned in the radial direction of the optical disk by a stepping motor driven feed screw or the like. Since the track of the optical disk slightly meanders, tracking to keep the position of application of the light on the track is performed by calculating a deviation from the track from the output of the light receiving element and moving the objective lens on the optical base.
When the optical base is moved by the feed screw, vibrations are applied to the optical base, and it is sometimes the case where the position of application of the light deviates from the target track (tracking error). Therefore, in the optical disk controller described in Patent Document 1, the influence of the vibrations of the optical base is suppressed by storing the vibratory waveforms expected to be applied to the optical base when the feed screw is driven by the stepping motor and increasing the gain of servo control of the tracking when vibrations are applied and correcting the set point of servo.
In this case, in order to allow the influence of the vibrations of the optical base to be reduced by gain adjustment of tracking control, the response of the tracking control must be sufficiently faster than the cycle of vibrations due to the feed screw. Moreover, complicated calculation attends to preparatorily store the vibratory waveforms due to the feed screw and to correct the control output of the tracking, and therefore, a high-speed processor is necessary.
Moreover, it is sometimes the case where an actuator to drive the lens for not only the tracking but also aberration correction is provided for the optical base of the optical pickup device. In this case, the optical base moves due to a reactive force of the driving of the actuator for the aberration correction, sometimes causing a tracking error.
The drive unit as described above provided for the optical base is a high-speed actuator generally coequal with the control speed of the objective lens. Therefore, gain adjustment cannot follow the movement, and the processing of reading the waveform stored in the memory takes excessive time, sometimes insufficiently functioning.
Patent Document 1: JP H09-180203 A